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Białek MJ, Hurej K, Furuta H, Latos-Grażyński L. Organometallic chemistry confined within a porphyrin-like framework. Chem Soc Rev 2023; 52:2082-2144. [PMID: 36852929 DOI: 10.1039/d2cs00784c] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
The world of modified porphyrins changed forever when an N-confused porphyrin (NCP), a porphyrin isomer, was first published in 1994. The replacement of one inner nitrogen with a carbon atom revolutionised the chemistry that one is able to perform within the coordination cavity. One could explore new pathways in the organometallic chemistry of porphyrins by forcing a carbon fragment from the ring or an inner substituent to sit close to an inserted metal ion. Since the NCP discovery, a series of modifications became available to tune the coordination properties of the cavity, introducing a fascinating realm of carbaporphyrins. The review surveys all possible carbatetraphyrins(1.1.1.1) and their spectacular coordination and organometallic chemistry.
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Affiliation(s)
- Michał J Białek
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50383 Wrocław, Poland.
| | - Karolina Hurej
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50383 Wrocław, Poland.
| | - Hiroyuki Furuta
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
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2
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Toganoh M, Furuta H. Creation from Confusion and Fusion in the Porphyrin World─The Last Three Decades of N-Confused Porphyrinoid Chemistry. Chem Rev 2022; 122:8313-8437. [PMID: 35230807 DOI: 10.1021/acs.chemrev.1c00065] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Confusion is a novel concept of isomerism in porphyrin chemistry, delivering a steady stream of new chemistry since the discovery of N-confused porphyrin, a porphyrin mutant, in 1994. These days, the number of confused porphyrinoids is increasing, and confusion and associated fusion are found in various fields such as supramolecular chemistry, materials chemistry, biological chemistry, and catalysts. In this review, the birth and growth of confused porphyrinoids in the last three decades are described.
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Affiliation(s)
- Motoki Toganoh
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hiroyuki Furuta
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
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Ren D, Liu B, Li X, Koniarz S, Pawlicki M, Chmielewski PJ. Reactions of 2-aza-21-carbaporphyrin with aniline derivatives. Org Chem Front 2019. [DOI: 10.1039/c9qo00024k] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Post-synthetic modification of N-confused porphyrin (NCP) yields chiral 21-arylazo- or 3,21-bis(arylamino)-NCP in one-step, one-pot reactions of NCP with anilines.
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Affiliation(s)
- Demin Ren
- College of Science
- Hunan Agricultural University
- Changsha 410128
- P. R. China
| | - Bin Liu
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Hunan University of Science and Technology
- Xiangtan
| | - Xiaofang Li
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Hunan University of Science and Technology
- Xiangtan
| | | | - Miłosz Pawlicki
- Department of Chemistry
- University of Wrocław
- 50 383 Wrocław
- Poland
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Idec A, Pawlicki M, Latos-Grażyński L. Ruthenium(II) and Ruthenium(III) Complexes of p-Benziporphyrin: Merging Equatorial and Axial Organometallic Coordination. Inorg Chem 2017; 56:10337-10352. [PMID: 28809478 DOI: 10.1021/acs.inorgchem.7b01237] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A diamagnetic ruthenium(II) complex of 5,10,15,20-tetraphenyl-p-benziporphyrin [RuII(p-BzP)(CO)Cl] was obtained via the insertion of ruthenium into p-benziporphyrin using triruthenium(0) dodecacarbonyl [Ru3(CO)12] as the metal source. The procedure applying dichloro(cycloocta-1,5-diene)ruthenium(II) (polymer, [Ru(COD)Cl2]n) afforded the paramagnetic six-coordinate ruthenium(III) p-benziporphyrin [RuIII(p-BzP)Cl2]. As shown by X-ray crystallography, the p-phenylene ring in both complexes is sharply tilted out of the N3 plane, as reflected by the respective N3 (pyrrole)-C6 (p-phenylene) dihedral angle [RuII(p-BzP)(CO)Cl, 52.5°; RuIII(p-BzP)Cl2, 53.7°]. p-Phenylene is bound to the ruthenium cation in an η2 fashion, revealing the shortest ever Ru-C distance in the series of p-benziporphyrin complexes [RuII(p-BzP)(CO)Cl, 2.275(2) Å; RuIII(p-BzP)Cl2, 2.324(5) Å]. The reaction of RuII(p-BzP)(CO)Cl with ArMgCl or AlkMgCl results in the formation of diamagnetic six-coordinate ruthenium(II) p-benziporphyrin complexes containing the apically coordinated σ-alkyl or σ-aryl ligands, where the metal ion simultaneously coordinates to three carbon centers respectively accommodating η2 (phenylene) and σ (aryl and alkyl) modes. Reactions of σ-aryl (alkyl) carbanions with paramagnetic RuIII(p-BzP)Cl2 have been followed by 1H NMR spectroscopy. The procedure afforded the six-coordinate paramagnetic ruthenium(III) p-benziporphyrin [RuIII(p-BzP)(Ph)Cl], which binds one σ-aryl ligand, as reflected by the characteristic 1H NMR spectra spread within the +120 to -120 ppm range. Both paramagnetic complexes RuIII(p-BzP)(Ph)Cl and RuIII(p-BzP)(p-Tol)Cl are formed as a mixture of two stereoisomers differentiated by two nonequivalent locations of σ-aryl with respect to the puckered macrocyclic ring. The paramagnetic shifts of σ-aryls are indicative of π-spin delocalization patterns. Analysis of the contact shifts and parallel density functional theory calculations of the spin density distribution in RuIII(p-BzP)Cl2, RuIII(p-BzP)(Ar)Cl, and RuIII(p-BzP)(Alk)Cl reflect the features of the dxy2(dxzdyz)3 electronic ground state.
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Affiliation(s)
- Aneta Idec
- Department of Chemistry, University of Wrocław , 14 F. Joliot-Curie Street, 50-383 Wrocław, Poland
| | - Miłosz Pawlicki
- Department of Chemistry, University of Wrocław , 14 F. Joliot-Curie Street, 50-383 Wrocław, Poland
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Investigation of agostic interaction through NBO analysis and its impact on β-hydride elimination and dehydrogenation: a DFT approach. Theor Chem Acc 2016. [DOI: 10.1007/s00214-016-1939-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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6
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Białek MJ, Białońska A, Latos-Grażyński L. Oxidation and Oxygenation of Carbonyl Ruthenium(II) Azuliporphyrin. Inorg Chem 2015; 54:6184-94. [DOI: 10.1021/acs.inorgchem.5b00324] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michał J. Białek
- Department of Chemistry, University of Wrocław, F.
Joliot-Curie 14, 50-383 Wrocław, Poland
| | - Agata Białońska
- Department of Chemistry, University of Wrocław, F.
Joliot-Curie 14, 50-383 Wrocław, Poland
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Zins EL, Silvi B, Alikhani ME. Activation of C–H and B–H bonds through agostic bonding: an ELF/QTAIM insight. Phys Chem Chem Phys 2015; 17:9258-81. [DOI: 10.1039/c4cp05728g] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
X–H agostic bonding: a topological insight.
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Affiliation(s)
- Emilie-Laure Zins
- Sorbonne Universités
- UPMC Univ. Paris 06
- MONARIS
- UMR 8233
- Université Pierre et Marie Curie
| | - Bernard Silvi
- Sorbonne Universités
- UPMC Univ. Paris 06
- Laboratoire de Chimie Théorique (LCT)
- UMR 7616
- Université Pierre et Marie Curie
| | - M. Esmaïl Alikhani
- Sorbonne Universités
- UPMC Univ. Paris 06
- MONARIS
- UMR 8233
- Université Pierre et Marie Curie
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8
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Tzeli D, Petsalakis ID, Theodorakopoulos G. Theoretical study on the electronic structure, formation and absorption spectra of lithium, sodium and potassium complexes of N-confused tetraphenylporphyrin. COMPUT THEOR CHEM 2013. [DOI: 10.1016/j.comptc.2013.07.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Myśliborski R, Rachlewicz K, Latos-Grażyński L. Low-spin organoiron(III) N-confused pyriporphyrin. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424607000229] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Oxidation of ( PyP H) Fe II Br , an iron(II) complex of 6,11,16,21-tetraaryl-3-aza-m-benziporphyrin ( N -confused pyriporphyrin, ( PyP H) H ) has been followed, in the presence of pyridine, by 1 H and 2 H NMR spectroscopy. One-electron oxidation with dioxygen, accompanied by deprotonation of a C (22) H fragment and formation of a Fe - C (22) bond, produced a low-spin, six-coordinate iron(III) complex [( PyP ) Fe III( py )2]+ as confirmed by combination of 1 H NMR, EPR and structural data. The characteristic patterns of 1 H NMR pyrrole and meso-aryl resonances resemble features assigned to the less common, low-spin ground electronic state (( d xz d yz )4( d xy )1) of iron(III) regular porphyrins. A conformational rearrangement process has been detected which involves two structures differentiated by macrocyclic ruffling. The structure of { H [( PyP ) Fe III( py )2]2}( Fe III Br 4)3· CH 2 Cl 2 has been determined by X-ray crystallography. The cationic complex involves a six-coordinate iron atom bound to the N -confused pyriporphyrin through its three nitrogens ( Fe - N (23) = 1.924(7), Fe - N (24) = 1.979(7), Fe - N (25) = 1.9343(7) Å) and the pirydyl trigonal C (22) atom ( Fe (1)- C (22) = 1.972(10) Å). The porphyrin is strongly ruffled, defining two deep grooves along C meso - C meso axes at right angles to each other. Two axial pyridine ligands are located in the prearranged equatorial ligand grooves. The iron lies in the N 3 C plane of the macrocycle defined by coordinating nitrogen and carbon atoms. In the solid, pairs of molecules are positioned along the line defined by Fe (1)- C (22) and Fe (2)- C (91) bonds. The structure demonstrates the head-to-head arrangement of two [( PyP ) Fe III( py )2]+ subunits revealing the adjacency of the two perimeter nitrogen atoms (the N (3)⋯ N (72) distance = 2.587(10) Å) linked by the N ⋯ H ⋯ N hydrogen bond.
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Affiliation(s)
- Radomir Myśliborski
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie St. Wrocław 50 383, Poland
| | - Krystyna Rachlewicz
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie St. Wrocław 50 383, Poland
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Maeda H, Furuta H. N-confused porphyrins as new scaffolds for supramolecular architecture. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424604000052] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The peripheral nitrogen of N -confused porphyrins ( NCP ) can serve as a hydrogen bonding donor and acceptor, and a metal coordination site as well. NCP forms versatile dimers with the assistance of metal ions such as Pd II, Pt II, Zn II, Cd II, Hg II, Mn II and Fe II. The square-planar divalent metal complexes of C 6 F 5-substituted NCP with Cu II, Ni II and Pd II act as efficient anion binding receptors. The doubly N -confused porphyrins ( N 2 CP ), possessing both N and NH at the periphery, form self-assembled 1-D hydrogen bonding networks, whose orientations differ in cis (zigzag) and trans (straight) isomers.
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Affiliation(s)
- Hiromitsu Maeda
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 812-8581, Japan
| | - Hiroyuki Furuta
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 812-8581, Japan
- PRESTO, Japan Science and Technology Corporation (JST), Japan
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11
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Toganoh M, Furuta H. Blooming of confused porphyrinoids—fusion, expansion, contraction, and more confusion. Chem Commun (Camb) 2012; 48:937-54. [DOI: 10.1039/c1cc14633e] [Citation(s) in RCA: 191] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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12
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Pacholska-Dudziak E, Gaworek A, Latos-Grażyński L. Iron(II) Vacataporphyrins: A Variable Annulene Conformation inside a Regular Porphyrin Frame. Inorg Chem 2011; 50:10956-65. [DOI: 10.1021/ic2015176] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ewa Pacholska-Dudziak
- Department of Chemistry, University of Wrocław, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland
| | - Aneta Gaworek
- Department of Chemistry, University of Wrocław, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland
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Chang GF, Wang CH, Lu HC, Kan LS, Chao I, Chen WH, Kumar A, Lo L, dela Rosa MAC, Hung CH. Factors That Regulate the Conformation of m-Benziporphodimethene Complexes: Agostic Metal-Arene Interaction, Hydrogen Bonding, and η2,π Coordination. Chemistry 2011; 17:11332-43. [DOI: 10.1002/chem.201100780] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Indexed: 11/06/2022]
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Ribas X, Calle C, Poater A, Casitas A, Gómez L, Xifra R, Parella T, Benet-Buchholz J, Schweiger A, Mitrikas G, Solà M, Llobet A, Stack TDP. Facile C-H bond cleavage via a proton-coupled electron transfer involving a C-H...Cu(II) interaction. J Am Chem Soc 2010; 132:12299-306. [PMID: 20712320 PMCID: PMC2937838 DOI: 10.1021/ja101599e] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The present study provides mechanistic details of a mild aromatic C-H activation effected by a copper(II) center ligated in a triazamacrocylic ligand, affording equimolar amounts of a Cu(III)-aryl species and Cu(I) species as reaction products. At low temperatures the Cu(II) complex 1 forms a three-center, three-electron C-H...Cu(II) interaction, identified by pulse electron paramagnetic resonance spectroscopy and supported by density functional theory calculations. C-H bond cleavage is coupled with copper oxidation, as a Cu(III)-aryl product 2 is formed. This reaction proceeds to completion at 273 K within minutes through either a copper disproportionation reaction or, alternatively, even faster with 1 equiv of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), quantitatively yielding 2. Kinetic studies of both reactions strongly implicate a rate-limiting proton-coupled electron transfer as the key C-H activation step, a mechanism that does not conform to the C-H activation mechanism in a Ni(II) analogue or to any previously proposed C-H activation mechanisms.
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Affiliation(s)
- Xavi Ribas
- Departament de Química, Universitat de Girona, Campus de Montilivi, E-17071, Girona, Catalonia (Spain)
| | - Carlos Calle
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, CH–8093 Zürich (Switzerland)
| | - Albert Poater
- Institut Català de Recerca de l’Aigua (ICRA), Parc Científic i Tecnològic, Universitat de Girona, Emili Grahit 101, E-17003, Girona, Catalonia (Spain)
| | - Alicia Casitas
- Departament de Química, Universitat de Girona, Campus de Montilivi, E-17071, Girona, Catalonia (Spain)
| | - Laura Gómez
- Departament de Química, Universitat de Girona, Campus de Montilivi, E-17071, Girona, Catalonia (Spain)
| | - Raül Xifra
- Departament de Química, Universitat de Girona, Campus de Montilivi, E-17071, Girona, Catalonia (Spain)
| | - Teodor Parella
- Servei de RMN, Universitat Autònoma de Barcelona, Bellaterra E-08193, Catalonia (Spain)
| | - Jordi Benet-Buchholz
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, E-43007 Tarragona, Catalonia (Spain)
| | - Arthur Schweiger
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, CH–8093 Zürich (Switzerland)
| | - George Mitrikas
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, CH–8093 Zürich (Switzerland)
| | - Miquel Solà
- Departament de Química, Universitat de Girona, Campus de Montilivi, E-17071, Girona, Catalonia (Spain)
- Institut de Química Computacional, Universitat de Girona, Campus Montilivi, Girona E-17071, Catalonia (Spain)
| | - Antoni Llobet
- Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, E-43007 Tarragona, Catalonia (Spain)
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Berlicka A, Latos-Grażyński L. Intramolecular Rotation of Iron(II) Dithiaethyneporphyrin Double-Decker Complex: 1H NMR Studies. Inorg Chem 2009; 48:7922-30. [DOI: 10.1021/ic900973d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anna Berlicka
- Department of Chemistry, University of Wrocław, 50 383 Wrocław, Poland
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16
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Zhu X, Jiang F, Poon C, Wong W, Wong W. Synthesis, Structure and Spectroscopic Properties of Lanthanide Complexes ofN‐Confused Porphyrins. Eur J Inorg Chem 2008. [DOI: 10.1002/ejic.200800267] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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17
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Chmielewski PJ. Synthesis and Characterization of Transition Metal Complexes of Dimeric N-Confused Porphyrin Linked by an o-Xylene Fragment. Inorg Chem 2008; 48:432-45. [DOI: 10.1021/ic800591n] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Piotr J. Chmielewski
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie Street, 50-383 Wrocław, Poland
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18
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Mankad N, Whited M, Peters J. Terminal FeIN2 and FeII⋅⋅⋅HC Interactions Supported by Tris(phosphino)silyl Ligands. Angew Chem Int Ed Engl 2007. [DOI: 10.1002/ange.200701188] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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19
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Mankad NP, Whited MT, Peters JC. Terminal FeIN2 and FeII⋅⋅⋅HC Interactions Supported by Tris(phosphino)silyl Ligands. Angew Chem Int Ed Engl 2007; 46:5768-71. [PMID: 17600810 DOI: 10.1002/anie.200701188] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Neal P Mankad
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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Pacholska‐Dudziak E, Latos‐Grażyński L. NMR Studies of Paramagnetic Metallocarbaporphyrinoids. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200700078] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ewa Pacholska‐Dudziak
- Department of Chemistry, University of Wrocław, 14 F. Joliot‐Curie St., Wrocław 50 383, Poland
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22
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Chmielewski PJ. Synthesis, Structure, and Redox Properties of N-Confused Bis(porphyrinatonickel(II)) Linked by o-Xylene. Inorg Chem 2007; 46:1617-26. [PMID: 17269762 DOI: 10.1021/ic061793e] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In a reaction of 5,10,15,20-tetraaryl-2-aza-21-carbaporphyrinato nickel(II) 2 with alpha,alpha'-dibromo-o-xylene, three different complexes containing a xylene moiety were obtained in the presence of a proton scavenger. The products were characterized by mass spectrometry, UV-vis, NMR, and, in the case of the dimeric complex 3, X-ray crystallographic analysis (space group P, a =16.455(3) A, b = 16.776(3) A, c = 18.400(4) A, alpha = 77.43(3) degrees , beta = 75.31(3) degrees , gamma = 66.20(3) degrees , V = 4457.1(19) A3, Z = 2). The monomeric species, diamagnetic 4 and paramagnetic 5, contain one and two bromoxylene residues, respectively, while in 3, the xylene bridge links two macrocyclic subunits, involving their internal carbons (C21) coordinated to diamagnetic nickel(II). Cyclovoltammetric measurements for o-xylene-linked bis(carbaporphyrinoid) 3 indicate cooperative effects resulting from an interaction between the subunits despite the isolation of their aromatic pi-bond systems. An EPR-controlled titration of 3 with bromine allows consecutive detection of the mono- and bis-oxidized species (3Br, 3Br2). The spectral patterns and spin-Hamiltonian parameters indicate metal-centered oxidation in 3Br (gx = 2.358, gy = 2.150, gz = 2.062, A(Br)x = 15, A(Br)y = 35, A(Br)z = 129 G) and interaction of two electron spins of nickel(III) ions in 3Br2 (gx = 2.328, gy = 2.195, gz = 2.065, D = 0.0173 cm(-)1, E = -0.0018 cm(-1), A(Br)z = 63 G). A product of the chemical reduction of a protonated form of the dimer was also detected by means of EPR (g1 = 2.298, g2 = 2.218, g3 = 2.192), although no interaction between the nickel(I) centers can be observed for the reduced species.
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Affiliation(s)
- Piotr J Chmielewski
- Department of Chemistry, University of Wroclaw, 14 F. Joliot-Curie Street, 50-383 Wroclaw, Poland.
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Rachlewicz K, Gorzelańczyk D, Latos-Grazyński L. Iron Complexes of C- and N-Methylated 2-Aza-21-carbaporphyrin: NMR Studies. Inorg Chem 2006; 45:9742-7. [PMID: 17112270 DOI: 10.1021/ic061092h] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Insertion of iron(II) into methylated derivatives of N-confused porphyrins 2-aza-2-methyl-5,10,15,20-tetraphenyl-21-carbaporphyrin (MeCTPPH)H, 2-aza-5,10,15,20-tetraphenyl-21-methyl-21-carbaporphyrin (CTPPMe)H2, and 2-aza-2-methyl-5,10,15,20-tetraphenyl-21-methyl-21-carbaporphyrin (MeCTPPMe)H yielded N- or C-methylated high-spin iron(II) complexes (MeCTPPH)Fe(II)Br, (HCTPPMe)Fe(II)Br, and (MeCTPPMe)Fe(II)Br. One electron oxidation of (Me-CTPPH)Fe(II)Br using Br2, accompanied by deprotonation of a C(21)-H(21) fragment and formation of an Fe-C(21) bond, produces an intermediate-spin, five-coordinate iron(III) complex (MeCTPP)Fe(III)Br. Simultaneously, a high-spin complex [(MeCTPPH)Fe(III)Br]+ was formed which preserved the side-on interaction between the metal ion and the inverted pyrrole ring. &[(MeCTPPH)Fe(III)Br]+ was also obtained by titration of (MeCTPP)FeIIIBr with TFA due to the C(21) protonation. A titration of (HCTPPMe)Fe(II)Br and (MeCTPPMe)Fe(II)Br with Br2 yielded solely corresponding high-spin iron(III) species [(HCTPPMe)Fe(III)Br+ and [(MeCTPPMe)Fe(III)Br+. Dioxygen reacts cleanly with (MeCTPPH)Fe(II)Br carbaporphyrin to form solely (MeCTPP)Fe(III)Br. The 1H NMR spectra of paramagnetic iron(II) and iron(III) complexes were examined. The characteristic patterns of pyrrole, C-methyl, and N-methyl resonances were found diagnostic of the ground electronic state of iron and the coordinating nature of the N-confused pyrrole. The characteristic C-Me resonances occur in a unique window (520-420 ppm) for iron(III) C-methylated N-confused porphyrins which remains in contrast with relatively small values found for iron(II) C-methylated derivatives (50-80 ppm).
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Affiliation(s)
- Krystyna Rachlewicz
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., Wrocław 50 383, Poland
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Myśliborski R, Rachlewicz K, Latos-Grazyński L. Iron Complexes of N-Confused Pyriporphyrin: NMR Studies. Inorg Chem 2006; 45:7828-34. [PMID: 16961375 DOI: 10.1021/ic060906r] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Insertion of iron(II) into 6,11,16,21-tetraaryl-3-aza-m-benziporphyrin (N-confused pyriporphyrin, (PyPH)H) yielded the high-spin iron(II) complex, (PyPH)Fe(II)Br. The coordination of iron(II) to the perimeter nitrogen atom of (PyPH)Fe(II)Br resulted in the formation of the diiron species. Oxidation and oxygenation of (PyPH)Fe(II)Br were followed by 1H NMR spectroscopy. The addition of Br2 to the solution of (PyPH)Fe(II)Br in the absence of dioxygen results in a one-electron oxidation yielding the high-spin iron(III) N-confused pyriporphyrin [(PyPH)Fe(III)Br]+ which preserves the side-on interaction between the inverted pyridine ring and metal ion. The reaction of (PyPH)Fe(II)Br with dioxygen ends up with the formation of a five-coordinate species (PyPO)Fe(III)Br] ((PyPOH)H = 3-aza-22-hydroxy-m-benziporphyrin, PyPO = the corresponding dianion) which is formed by oxygenation at the C(22) position. Coordination of a metal ion by 3-aza-22-hydroxy-benziporphyrin imposes a steric constraint on the geometry of the ligand. The halide ligand of (PyPO)Fe(III)Br coordinates on one of the two inequivalent faces of the macrocycle, leading to two distinct species: syn and anti. The (1)H NMR spectra of paramagnetic iron(II) and iron(III) N-confused pyriporphyrin complexes have been examined. The characteristic patterns of pyrrole and pyridine resonances have been found to be diagnostic of the ground electronic state of iron and the donor nature of the C(22)H and N(3) centers. The enormous downfield H(22) paramagnetic shift, determined for the iron(II) N-confused pyriporphyrin, provides a distinct resonance in a peculiar spectroscopic window (350-800 ppm) for a series of axial ligands which can be considered as a diagnostic sign of an agostic Fe(II)...{C(22)-H} interaction. Coordination of the pyridine moiety via the perimeter N(3) atom is reflected unambiguously by the H(2/4) resonance at 201 ppm.
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Affiliation(s)
- Radomir Myśliborski
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie Street, Wrocław 50 383, Poland
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Harvey JD, Ziegler CJ. The metal complexes of N-confused porphyrin as heme model compounds. J Inorg Biochem 2006; 100:869-80. [PMID: 16510190 DOI: 10.1016/j.jinorgbio.2006.01.016] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 01/10/2006] [Accepted: 01/10/2006] [Indexed: 11/25/2022]
Abstract
Recently, metal complexes of the isomers and analogs of porphyrin have become important model compounds for heme enzymes and proteins. While the chemistry of metalloporphyrins as heme models still attracts attention, the isomers and analogs of porphyrins provide insight into the biological choice of porphine as the macrocycle of choice and also help model reactive intermediates, such as high valent oxidation states. In this mini-review, we discuss the heme-relevant chemistry of N-confused porphyrin, an isomer of porphyrin with an inverted pyrrole ring, and focus on the chemistry of manganese, iron, and cobalt. The metallation chemistry of this macrocycle is more diverse than normal porphyrin, and involves tautomerization, C-H bond activation, the Lewis basicity of the external nitrogen, and issues with nucleophilic sensitivity. Despite the challenges posed by N-confused porphyrin, significant progress has been made toward generating heme-model complexes with this macrocycle.
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Affiliation(s)
- John D Harvey
- Department of Chemistry, Buchtel College of Arts and Sciences, University of Akron, KNCL 404, Akron, OH 44325-3601, USA
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Hung CH, Chang CH, Ching WM, Chuang CH. Molecular assembling using axial phenolate on an iron N-confused porphyrin complex. Chem Commun (Camb) 2006:1866-8. [PMID: 16622511 DOI: 10.1039/b600423g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of sodium phenolate and Fe(HCTPPH)Br assembles a dimeric iron(III) complex with a channel-like solid state packing; the intramolecular iron-to-iron distance of 8.864 A is the longest among the available N-confused porphyrin dimeric complexes.
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Affiliation(s)
- Chen-Hsiung Hung
- Institute of Chemistry, Academia Sinica, Nankang Taipei, 105 Taiwan.
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Pawlicki M, Latos-Grazyński L. O-confusion approach in construction of carbaporphyrinoids. CHEM REC 2006; 6:64-78. [PMID: 16565985 DOI: 10.1002/tcr.20072] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Carbaporphyrinoids provide a suitable macrocyclic platform for organometallic investigations providing unique capabilities for reversible modifications of a macrocyclic structure. Alteration of a coordination core is the route of choice for stabilizing unusual metal ion oxidation states and coordination geometries. This concise review presents the general characteristic of carbaporphyrinoid focusing, however, on oxaporphyrin derivatives. Incorporation of a furan ring into a porphyrin frame results in the formation of 21-oxaporphyrin or its O-confused counterpart. This particular couple, constructed applying the O-confusion concept, was selected to illustrate the developments in the field of carbaporphyrinoids. The coordination chemistry in the O-confused porphyrin surrounding takes advantage of the unique set of four meridional donor atoms (CNNN) constrained in the regular porphyrin-like framework. The subtle interplay between their structural flexibility, perimeter substitution, coordination, and aromaticity was detected for oxacarbaporphyrinoids. The oxidation state of a central metal ion is a factor, which determines the ligand molecular structure. The adjacency of the metal and carbon atom provides the unprecedented route for activation of the carbocyclic moiety, which is built into a metalloporphyrin-like structure. The perspectives of the field have also been briefly discussed including feasible applications as a new class of building blocks applied to control both the architecture and electronic properties of oligoporphyrinic nanostructures.
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Affiliation(s)
- Miłosz Pawlicki
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., Wrocław 50 383, Poland
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Pawlicki M, Latos-Grazyński L, Szterenberg L. Cadmium(II) and Zinc(II) Complexes of Pyrrole-Appended Oxacarbaporphyrin: A Side-on Coordination Mode of O-Confused Carbaporphyrin. Inorg Chem 2005; 44:9779-86. [PMID: 16363847 DOI: 10.1021/ic051238x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A pyrrole adduct of 5,20-diphenyl-10,15-di(p-tolyl)-2-oxa-21-carbaporphyrin [(H,pyr)OCPH]H(2) reacted with sodium ethanolate to yield 5,20-diphenyl-10,15-di(p-tolyl)-3-ethoxy-3-(2'-pyrrol)-2-oxa-21-carbaporphyrin [(EtO,pyr)OCPH]H(2). Subsequently, "true" O-confused oxaporphyrin with a pendant pyrrole ring [(pyr)OCPH]H was formed by the addition of acid to [(EtO,pyr)OCPH]H(2), which triggered an ethanol elimination. In the course of this process, the tetrahedral-trigonal rearrangements originated at the C(3) atom. Insertion of zinc(II), cadmium(II), and nickel(II) into [(pyr)OCPH]H yielded [(pyr)OCPH]Zn(II)Cl, [(pyr)OCPH]Cd(II)Cl, and [(pyr)OCP]Ni(II). The formation of [(pyr)OCP]Ni(II) was accompanied by the C(21)H dehydrogenation step. The nickel(II) ion of [(pyr)OCP]Ni(II), coordinated to a dianionic macrocyclic ligand, is bound by three pyrrolic nitrogens and a trigonally hybridized C(21) atom of the inverted furan. The pyrrole-appended O-confused carbaporphyrin acts as a monoanionic ligand toward zinc(II) and cadmium(II) cations. Three nitrogen atoms and the C(21)H fragment of the inverted furan occupy equatorial positions. In (1)H NMR spectra, the unique inner C(21)H resonances of the inverted furan ring are located at 0.15 ppm for [(pyr)OCPH]Zn(II)Cl, and at 0.21 ppm for [(pyr)OCPH]Cd(II)Cl. The proximity of the furan fragment to the metal ion induces direct scalar couplings between the spin-active nucleus of the metal ((111/113)Cd) and the adjacent (1)H nucleus. The interaction of the metal ion and C(21)H was also reflected by significant changes in carbon chemical shifts ([(pyr)OCPH]Zn(II)Cl, 78.3 ppm; [(pyr)OCPH]Cd(II)Cl, 81.4 ppm; the free base, 101.3 ppm). The density functional theory (DFT) has been applied to model the molecular structures of zinc(II) and cadmium(II) complexes of O-confused oxaporphyrin with an appended pyrrole ring. The Cd...C(21) distance in the optimized structure exceeds the typical Cd-C bond lengths, but is much shorter than the corresponding van der Waals contact.
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Affiliation(s)
- Miłosz Pawlicki
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie Street, Wrocław 50 383, Poland
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Chmielewski PJ, Latos-Grażyński L. Core modified porphyrins – a macrocyclic platform for organometallic chemistry. Coord Chem Rev 2005. [DOI: 10.1016/j.ccr.2005.05.015] [Citation(s) in RCA: 204] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Stepień M, Latos-Grazyński L. Benziporphyrins: exploring arene chemistry in a macrocyclic environment. Acc Chem Res 2005; 38:88-98. [PMID: 15709728 DOI: 10.1021/ar040189+] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Benziporphyrins are synthetic porphyrin analogues, in which one of the pyrroles is replaced with a benzenoid ring. The arene can be incorporated into the macrocycle in several ways leading to molecules with distinct physical and chemical properties. By appropriately changing the structure of benziporphyrins, it is possible to affect their aromaticity, tautomeric equilibria, and reactivity. Benziporphyrins are versatile ligands, which offer a means to study the metal-arene couple in a macrocyclic environment. The coordination brings the metal ion into the vicinity of the arene fragment leading to activation of C-H bonds or weak interactions, which can be observed spectroscopically.
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Affiliation(s)
- Marcin Stepień
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie Street, Wrocław 50383, Poland
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Eckert NA, Smith JM, Lachicotte RJ, Holland PL. Low-coordinate iron(II) amido complexes of beta-diketiminates: synthesis, structure, and reactivity. Inorg Chem 2004; 43:3306-21. [PMID: 15132641 DOI: 10.1021/ic035483x] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis, structure, and reactivity of a series of low-coordinate Fe(II) diketiminate amido complexes are presented. Complexes L(R)FeNHAr (R = methyl, tert-butyl; Ar = para-tolyl, 2,6-xylyl, and 2,6-diisopropylphenyl) bind Lewis bases to give trigonal pyramidal and trigonal bipyramidal adducts. In the adducts, crystallographic and (1)H NMR evidence supports the existence of agostic interactions in solid and solution states. Complexes L(R)FeNHAr may be oxidized using AgOTf, and the products L(R)Fe(NHAr)(OTf) are characterized with (19)F NMR spectroscopy, UV/vis spectrophotometry, solution magnetic measurements, elemental analysis, and, in one case, X-ray crystallography. In the structures of the iron(III) complexes L(R)Fe(NHAr)(OTf) and L(R)Fe(OtBu)(OTf), the angles at nitrogen and oxygen result from steric effects and not pi-bonding. The reactions of the amido group of L(R)FeNHAr with weak acids (HCCPh and HOtBu) are consistent with a basic nitrogen atom, because the amido group is protonated by terminal alkynes and alcohols to give free H(2)NAr and three-coordinate acetylide and alkoxide complexes. The trends in complex stability give insight into the relative strength of bonds from three-coordinate iron to anionic C-, N-, and O-donor ligands.
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Affiliation(s)
- Nathan A Eckert
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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Hung CH, Chang FC, Lin CY, Rachlewicz K, Stepień M, Latos-Grazyński L, Lee GH, Peng SM. Iron and Copper Complexes of Tetraphenyl-m-benziporphyrin: Reactivity of the Internal C−H Bond. Inorg Chem 2004; 43:4118-20. [PMID: 15236521 DOI: 10.1021/ic049821l] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Iron and copper complexes of tetraphenyl-m-benziporphyrin (TPmBPH)H have been prepared and structurally characterized. The iron system, (TPmBPH)Fe(II)Br, contains a high-spin Fe(II) center. In the solid state the complex forms dimeric units linked by weak CH.Br hydrogen bonds. The Cu complex contains a tetrameric copper cluster with a Cu(2)Cl(4)(2)(-) unit bridging two [(TPmBPCl)Cu(II)](+) fragments. The formation of (TPmBPCl)H represents an example of copper-catalyzed chlorination on the internal carbon atom of (TPmBPH)H.
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Affiliation(s)
- Chen-Hsiung Hung
- Department of Chemistry, National Changhua University of Education, Changhua 50058, Taiwan.
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Stepień M, Latos-Grazyński L, Szterenberg L, Panek J, Latajka Z. Cadmium(II) and Nickel(II) Complexes of Benziporphyrins. A Study of Weak Intramolecular Metal−Arene Interactions. J Am Chem Soc 2004; 126:4566-80. [PMID: 15070375 DOI: 10.1021/ja039384u] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Weak metal-arene interactions have been investigated in Zn, Cd, Hg, and Ni complexes of meso-tetraaryl m- and p-benziporphyrin (1 and 2) and of the new compound, m-benziporphodimethene (3). Compounds 1-3 incorporate the phenylene moiety into a macrocyclic structure so as to facilitate the interaction between the arene and coordinated metal ion. X-ray studies performed on Cd(II) and Ni(II) complexes show that the arene fragment approaches the ion at a distance much shorter than the sum of van der Waals radii. In chloronickel(II) m-benziporphyrin, a weak agostic bond is actually formed. In the NMR spectra of the Cd(II) and Hg(II) species, unusual (1)H-M and (13)C-M scalar couplings have been observed that are transmitted directly between the metal and the arene. DFT calculations performed for two Cd(II) species and subsequent AIM analysis show that the accumulation of electron density between the metal and arene necessary to induce these couplings is fairly small and the interaction is steric in nature. In the paramagnetic Ni(II) complexes of 1 and 3, the agostic proton of the m-phenylene exhibits large downfield (1)H NMR shifts (386 and 208 ppm at 298 K, respectively). An agostic mechanism of spin density transfer is proposed to explain these shifts as resulting from electron donation from the CH bond to the metal. In chloronickel(II) p-benziporphyrin, the inner protons of the p-phenylene have a contrastingly small shift (0.0 ppm at 298 K), indicating that in this case the agostic interaction is inefficient, in agreement with the X-ray data.
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Affiliation(s)
- Marcin Stepień
- Department of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., Wrocław 50 383, Poland
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Rachlewicz K, Wang SL, Ko JL, Hung CH, Latos-Grazyński L. Oxidation and Oxygenation of Iron Complexes of 2-Aza-21-carbaporphyrin. J Am Chem Soc 2004; 126:4420-31. [PMID: 15053632 DOI: 10.1021/ja039792y] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidation and oxygenation of (HCTPPH)Fe(II)Br an iron(II) complex of 2-aza-5,10,15,20-tetraphenyl-21-carbaporphyrin (CTPPH)H2 have been followed by 1H and 2H NMR spectroscopy. Addition of I2 or Br2 to the solution of (HCTPPH)Fe(II)Br in the absence of dioxygen results in one-electron oxidation yielding [(HCTPPH)Fe(III)Br]+. One electron oxidation with dioxygen, accompanied by deprotonation of a C(21)H fragment and formation of an Fe-C(21) bond, produces an intermediate-spin, five-coordinate iron(III) complex (HCTPP)Fe(III)Br. In the subsequent step an insertion of the oxygen atom into the preformed Fe(III)-C(21) bond has been detected to produce [(CTPPO)Fe(III)Br]-. Protonation at the N2 atom affords (HCTPPO)Fe(III)Br. The considered mechanism of (HCTPPH)Fe(II)Br oxygenation involves the insertion of dioxygen into the Fe-C bond. The 1H NMR and 2H NMR spectra of paramagnetic iron(III) complexes were examined. Functional group assignments have been made with use of selective deuteration. The characteristic patterns of pyrrole and 2-NH resonances have been found diagnostic of the ground electronic state of iron and the donor nature localized at C(21) center as exemplified by the 1H NMR spectrum of intermediate-spin (HCTPP)Fe(III)Br: beta-H 7.2, -10.6, -19.2, -20.6, -23.2, -24.9, -43.2; 2-NH -76.6 (ppm, 298 K). The structures of two compounds (HCTPP)Fe(III)Br and (HCTPPO)Fe(III)Br, were determined by X-ray diffraction studies. In the first case, the iron(III) is five-coordinate with bonds to three pyrrole nitrogen atoms (Fe-N distances: 1.985(8), 2.045(7), 2.023(8) A), and the pyrrolic trigonal carbon (Fe-C: 1.981(8) A). The iron(III) of (HCTPPO)Fe(III)Br forms bonds to three pyrrole nitrogen atoms (Fe-N distances 2.104(5), 2.046(5), 2.102(5) A). The Fe-O 2.041(5) A and Fe-C(21) 2.192(5) A distances suggests a direct interaction between the iron center and the pi electron density on the carbonyl group in a eta2 fashion.
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